Lathe

ABSTRACT

A lathe has a bedplate to which is mounted a lathe bed defining first and second slideways and a fixed headstock holding a rotatable spindle. A movable tailstock slides on at least one of the slideways such that the spindle axis lies in a first plane and the first and second slideways lie in a common second plane perpendicular to the first plane and equally spaced therefrom.

United States Patent 1191 Wolff Jan. 15, 1974 LATHE [75] Inventor: PaulWolff, lllkirch Graffenstaden,

France [73] Assignee: Compagnie lndustrielle Des TelecommunicationsCit-Alcatel, Paris, France [22] Filed: Oct. 14, 1971 [21] Appl. No.:189,421

[30] Foreign Application Priority Data Oct. 14, 1970 France 7037161 [56]References Cited UNITED STATES PATENTS 3/1964 Curtis et a1. 82/2 R12/1961 Waldrich 82/32 R 3/1951 Brandenburg 82/32 R 2,255,739 9/1941Curtis 82/21 R X 1,528,971 3/1925 Groene v 82/2 R 3,600,987 8/1971Kuanskkam. 82/1 R 3,372,613 3/1968 Feld 82/24 3,332,458 7/1967 Baldwin82/32 R X 2,010,557 8/1935 Nenninger et a1. 82/32 R X FOREIGN PATENTS ORAPPLICATIONS 964,425 7/1964 Great Britain 82/32 262,032 9/1949Switzerland 82/32 644,182 4/1937 Germany 82/32 Primary Examiner-HarrisonL. Hinson Att0rneySughrue, Rothwell, Mion, Zinn & Macpeak [57] ABSTRACTA lathe has a bedplate to which is mounted a lathe bed defining firstand second slideways and a fixed headstock holding a rotatable spindle.A movable tailstock slides on at least one of the: slideways such thatthe spindle axis lies in a first plane and the first and secondslideways lie in a common second plane perpendicular to the first planeand equally spaced therefrom.

21 Claims, 6 Drawing Figures PAIEMEU I 378522? SHEET 1 BF 6 PATENTEBJAN15 I974 sum 2 or 6 FIG.2

PATENTEDJANISIQH 3.785.227

sum 3 0F 6 FIG.3

PAIENTEDJANIBW 3.m5.227

SHEEI a 0F 6 PATENTED JAN 1 51974 SHEEISBFS LATHE BACKGROUND OF THEINVENTION 1. Field of the Invention The present invention concerns animproved lathe.

2. Description of the Prior Art The conventional lathe generallycomprises a lathe bed mounting one or more tool-carrying carriages, the

workpiece being fixed between a spindle carried in a headstock and acenter mounted in a sleeve carried by a movable tailstock. Theseelements are generally mounted on a plinth or bedplate resting on theground.

A disadvantage of the conventional lathe is that the possibilities foradapting it and modifying it to unusual applications are severelylimited. The interchanging of the lathe elements and their arrangementsin various combinations is generally difficult, if not impossible. Thus,the adaptation of a conventional lathe to a particular job to be donecan involve drastic modifications, often at great expense.

A second disadvantage is that the axes of the spindle and center aresubject to displacements, particularly with respect to the toolpositions. Such displacements may be due to heating caused by thespindle rotation, or to heat coming from adjacent elements, for example.The precision of the work which may be carried out on such machines istherefore limited.

Conventional machines are generally mounted on a plinth resting on theground, and associated elements such as hydraulic supplies, electricalequipment and so on are placed next to the plinth. The installation andhandling of such machines poses difficulties, and the machine isverysensible to shocks and vibrations originating in the surroundings.

The conventional machines are fixed to the ground by means of a set oflevelling concrete screws more than three in number. Their installationtherefore poses problems, the adjustment of the levelling screwsproducing deformations in the machine, and these may vary with time.

In conventional machines, the number of toolholding carriages which maybe mounted is strictly limited, which produces a significant increase inthe machining time for certain types of work.

These carriages are generally mounted on slideways without any form ofprotection against turnings, so that there is a risk that the carriageswill become jammed by these turnings, particularly when'workpieces in ahard metal are being treated.

SUMMARY OF THE INVENTION In accordance with the present invention alathe comprises a bedplate on which are mounted a lathe bed definingfirst and second slideways and a fixed headstock holding a rotatablespindle, a movable tailstock on at least one of the slideways, and meansfor maintaining the spindle axis in a first plane, the first and secondslideways lying in a common second plane perpendicular to the first andbeing equally spaced from the first plane.

The invention will now be described in more detail, by way of exampleonly and with reference to the accompanying diagrammatic drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of alathe.

FIG. 2 is a similar view of the lathe, mounted on its bedplate and withcertain elements removed.

FIG. 3 is a front elevation of the lathe.

FIGS. 4a and 4b show a tool-holding carriage of the lathe.

FIG. 5 is a section through the carriage to a larger scale.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, the latheincludes a lathe bed 1 formed as a single casting and defining first andsecond pairs of slideways 2 and 3, hereinafter referred to as the upperand lower slideways respectively. Each slideway is defined by a pair ofrails.

On the upper slideway 2 is mounted the movable tailstock 4 carrying thecenter assembly indicated generally at 5. This assembly 5 comprises thecenter sleeve 16 in which the center 17 is mounted.

A saddle 6 is mounted on the lower slideway 3, and carries a protectivecover 7. On this saddle 6 is mounted a carriage 8 carrying a tool 9. Thesaddle 6 slides horizontally along the lower slideway 3, and thecarriage 8 slides vertically on slideways formed on the saddle.

Attached to the lathe bed I is a headstock indicated generally at 10.This carries a spindle on which is mounted a chuck 11. This spindle andthe center 17 are coaxial, their common axis lying in a horizontal firstplane. The upper and lower slideways 2 and 3 lie in a common verticalsecond plane, and are equally spaced from the first plane.

Below the chuck 11 and center 17 is mounted a hopper 12 for the turningsproduced during operation.

Referring to FIG. 2, the lathe bed I is formed with a first aperture 13between the upper and lower slideway 2 and 3. A second aperture 14 isformed below the lower slideway 3. The lathe bed 1 and the headstock 10are mounted on a bedplate 15 in which are formed three substantiallyvertical bores 18. In each of these is located a respective peg or foot19, each foot being longer than the bore 18 in which it is located,whereby the lathe rests on the ground on three points only.

The bedplate I5 is attached to the lathe bed I by means of bolts 21, andmay therefore be used to mount various ancillary elements of the lathe,such as the motor and geared transmission, electrical equipment and soon. The bedplate also provides a support for the turnings hopper 12,which may be fixed to the bedplate and provided with means forautomatically removing turnings from the hopper.

The headstock 10 comprises a base 30 on which is disposed one half ofthe bearing for the lathe spindle. The upper half of this bearing isdefined by a spindle mount 31, the bearing being divided in the planecontaining the axis X--X of the spindle and center. The mount 31 isbolted to the support 30 along one side only, by means of bolts 33, toallow free lateral expansion. The base 30 and mount 31 are separated bya layer 32 of thermally insulative material.

This arrangement of the headstock provides a free play for theexpansions and contractions due to rotation of the spindle, the axis X-Xremaining always in the first plane, that of the layer 32.

The lathe elements so far mentioned are interchangeable, and lead tovarious possible combinations. For example, the headstock may be mountedat either the left-hand or the right-hand end of the lathe bed 1. Ifrequired, two headstocks may be attached to the same lathe bed. Thelathe spindle may be mounted in the headstock so as to face in eitherdirection, as may the center l7 in the tailstock. The tailstock may bemounted on either the upper slideway 2 or the lower slideway 3 the pairsof slideways being symmetrical relative to the plane passing through theheadstock spindle axis.

The saddle 6 may be mounted on either slideway, and may carry more thanone carriage. Further saddles may be mounted on the same slideway, orsaddles may be mounted on both slideways, each with the appropriatenumber of carriages to carry out any particular type of work. A singlesaddle may be mounted on both slideways 2 and 3, carrying one or morecarriages.

The upper aperture 13 may house one or more toolcarrying carriagesmounted on guide strips (not shown) formed on the lathe bed 1. Theaperture 13 may also house handling means for the workpieces,particularly where a row of similar lathes are arranged in a productionline.

The lower aperture 14 may house a copying device, of any suitable knowntype.

The lathe just described is highly adaptable, permitting numerous kindsof work to be carried out. For example, a saddle 6 may be mounted oneach of the slideways 2 and 3, each with one tool-carrying carriage. Athird carriage may be mounted in the upper aperture 13, so that acylindrical workpiece may be attached at each of three generatricesseparated by 90.

With the tailstock removed from the lathe bed 1, a saddle may be mountedon slideways 2 and 3 carrying a single tool-holding carriage with whichthe ends of a workpiece held in the chuck 11 may be treated.

FIG. 3 is a front elevation of the lathe, showing the elements so fardescribed, a saddle 6 being mounted on each of the slideways 2 and 3.FIG. 3 also shows the geared transmission 40 and the electric motor 41with which the lathe spindle is driven. The motor and transmissionassembly may be mounted on either side of the headstock 10, depending onwhich end of the lathe bed 1 the headstock is mounted.

The motor and transmission assembly is attached to the headstock, bybolts 42 for example, so as to leave a thermally-insulative space 43between them, the number of points of contact being reduced to aminimum. The transfer of heat between the motor and transmission and theheadstock is thus reduced to a very low value, aiding maintenance of theaxis XX in the first plane.

The sleeve 16 is held in the headstock 4 in a bearing divided in thefirst plane. A layer of thermally insulative material 44 is locatedbetween the bearing parts, serving the same function as the layer 32 inthe headstock 10.

Referring to FIG. 4a, the saddle 6 carried on the slideway 2 mounts atool-carrying carriage indicated generally at 8. This comprises a fixedpart 50 attached to the saddle 6 by means of a dovetail joint 51 at oneend and an L-shaped flange 52 at its other end. This fixed portiondefines slideways 53 on which is mounted a movable portion 54 of thecarriage. An apertured protective cover 55 is attached to the carriage8, the aperture 56 allowing free movement of the movable carriageportion 54 along the slideways 53.

FIG. 4b shows the cover 55 in place on the carriage 8, and also showstwo sheets of foil, 57 and 58 respectively, each fixed at one end to oneend of the movable carriage portion 54. These sheets of foil slidefreely within the cover 55, and are so arranged that the aperture 56 isalways obscured, so preventing entry of turnings into the cover, andavoiding the risk that the movable carriage portion 54 will be jammed onits slideways 53 by such turnings. FIG. 5 is a section through the lowerpart of the carriage 8, showing the disposition of the foil sheets.

The lower foil sheet 58 is attached at its upper end to the lower end ofthe movable carriage portion 54, by screws 59. The foil sheet restsfreely inside the cover 55, and it will be seen that as the movablecarriage portion is raised from its lowermost position (that shown inthe Figure), the foil sheet will be raised to continuously obscure thelower part of the aperture 56. A turnings ejector 60 is fitted to thelower end of the aperture 56, so that no turnings may fall onto andremain on the rim of the aperture.

What is claimed is:

l. A lathe comprising:

a bedplate,

a lathe bed mounted on said bedplate defining first and second pairs ofslideways,

a fixed headstock attached to said lathe bed and holding a rotatablespindle,

a movable tailstock on one of the pairs of slideways,

means for maintaining the spindle axis in a first plane,

and said first and second pairs of slideways lying in a common secondplane perpendicular to the first plane and being equally spaced from thefirst plane and being symmetrical to permit said tailstock to beinterchangeably carried by either pairs of slideways.

2. A lathe as claimed in claim 1, wherein: the lathe bed is formed witha first aperture between the first and second pairs of slideways.

3. A lathe as claimed in claim 2, wherein: the first aperture houses atleast one carriage.

4. A lathe as claimed in claim 2, wherein: the first aperture houses atleast one device for handling workpieces of the lathe.

5. A lathe as claimed in claim 1, wherein: the headstock bearing for thespindle is split in the first plane and the means for maintaining thespindle axis in the first plane comprises a layer ofthermally-insulative material between the bearing segments.

6. A lathe as claimed in claim 4, wherein: the headstock bearing for thespindle is split in the first plane and the means for maintaining thespindle axis in the first plane comprises a layer of thermallyinsulative material between the bearing segments.

7. A lathe as claimed in claim 1, wherein: a sleeve is mounted withinthe tailstock and carries a center coaxial with the spindle, and saidlathe further includes means for maintaining the center axis in thefirst plane.

8. A lathe as claimed in claim 7, wherein: the sleeve mounting isdivided in the first plane and the means for maintaining the center axisin the first plane comprises a layer of thermally insulative materialbetween the sleeve mounting sections.

9. A lathe as claimed in claim 2, wherein the lathe bed is formed with asecond aperture on that side of the one pair of slideways remote fromthe first aperture.

10. A lathe as claimed in claim 9, wherein: the second apertureaccommodates a copying device.

11. A lathe as claimed in claim 1, including at least one saddle mountedon at least one of the slideways and at least one carriage mounted oneach saddle, and wherein each set of carriage slideways is protectedfrom the lathe turnings by a sheet of foil attached at one of its endsto each end of the respective carriage.

12. A lathe as claimed in claim 11, wherein each carriage is providedwith an apertured protective cover, the sheets of foil at each end ofthe carriage sliding freely within the cover.

13. A lathe as claimed in claim 1, including three bores in the bedplatehousing respective feet on which the lathe bed and headstock aresupported.

14. A lathe as claimed in claim 13, wherein the bedplate is attached tothe lathe bed by means of bolts.

15. A lathe as claimed in claim 13, wherein the length of the feetexceeds the thickness of the bedplate.

16. A lathe as claimed in claim 1, wherein the means of mounting thelathe bed and headstock on the bedplate are so arranged that the:headstock may be mounted at the right-hand or left-hand end of the lathebed.

17. A lathe as claimed in claim 16, in which the means of mounting thespindle on the headstock allow the spindle to face either way on theheadstock.

18. A lathe as claimed in claim 16, wherein the means of mounting thecenter in the tailstock allow the center to face either way in thetailstock.

19. The lathe as claimed in claim 16, further including a motor andgeared transmission for driving the spindle and means for mounting themotor and transmission on either side of the headstock.

20. A lathe as claimed in claim 19, wherein the motor and transmissionare mounted on the headstock in such a way as to reduce the area ofcontact therebetween to a minimum.

21. A lathe as claimed in claim 20, wherein a'thermally-insulative spaceis provided between the motor and transmission assembly and theheadstock.

1. A lathe comprising: a bedplate, a lathe bed mounted on said bedplatedefining first and second pairs of slideways, a fixed headstock attachedto said lathe bed and holding a rotatable spindle, a movable tailstockon one of the pairs of slideways, means for maintaining the spindle axisin a first plane, and said first and second pairs of slideways lying ina common second plane perpendicular to the first plane and being equallyspaced from the first plane and being symmetrical to permit saidtailstock to be interchangeably carried by either pairs of slideways. 2.A lathe as claimed in claim 1, wherein: the lathe bed is formed with afirst aperture between the first and second pairs of slideways.
 3. Alathe as claimed in claim 2, wherein: the first aperture houses at leastone carriage.
 4. A lathe as claimed in claim 2, wherein: the firstaperture houses at least one device for handling workpieces of thelathe.
 5. A lathe as claimed in claim 1, wherein: the headstock bearingfor the spindle is split in the first plane and the means formaintaining the spindle axis in the first plane comprises a layer ofthermally-insulative material between the bearing segments.
 6. A latheas claimed in claim 4, wherein: the headstock bearing for the spindle issplit in the first plane and the means for maintaining the spindle axisin the first plane comprises a layer of thermally insulative materialbetween the bearing segments.
 7. A lathe as claimed in claim 1, wherein:a sleeve is mounted within the tailstock and carries a center coaxialwith the spindle, and said lathe further includes means for maintainingthe center axis in the first plane.
 8. A lathe as claimed in claim 7,wherein: the sleeve mounting is divided in the first plane and the meansfor maintaining the center axis in the first plane comprises a layer ofthermally insulative material between the sleeve mounting sections.
 9. Alathe as claimed in claim 2, wherein the lathe bed is formed with asecond aperture on that side of the one pair of slideways remote fromthe first aperture.
 10. A lathe as claimed in claim 9, wherein: thesecond aperture accommodates a copying device.
 11. A lathe as claimed inclaim 1, including at least one saddle mounted on at least one of theslideways and at least one carriage mounted on each saddle, and whereineach set of carriage slideways is protected from the lathe turnings by asheet of foil attached at one of its ends to each end of the respectivecarriage.
 12. A lathe as claimed in claim 11, wherein each carriage isprovided with an apertured protective cover, the sheets of foil at eachend of the carriage sliding freely within the cover.
 13. A lathe asclaimed in claim 1, including three bores in the bedplate housingrespective feet on which the lathe bed and headstock are supported. 14.A lathe as claimed in claim 13, wherein the bedplate is attached to thelathe bed by means of bolts.
 15. A lathe as claimed in claim 13, whereinthe length of the feet exceeds the thickness of the bedplate.
 16. Alathe as claimed in claim 1, wherein the means of mounting the lathe bedand headstock on the bedplate are so arranged that the headstock may bemounted at the right-hand or left-hand end of the lathe bed.
 17. A latheas claimed in claim 16, in which the means of mounting the spindle onthe headstock allow the spindle to face either way on the headstock. 18.A lathe as claimed in claim 16, wherein the means of mounting the centerin the tailstock allow the center to face either way in the tailstock.19. The lathe as claimed in claim 16, further including a motor andgeared transmission for driving the spindle and means for mounting themotor and transmission on either side of the headstock.
 20. A lathe asclaimed in claim 19, wherein the motor and transmission are mounted onthe headstock in such a way as to reduce the area of contacttherebeTween to a minimum.
 21. A lathe as claimed in claim 20, wherein athermally-insulative space is provided between the motor andtransmission assembly and the headstock.